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////////////////////////////////////////////////////////////////////////////////
// The Loki Library
// Copyright (c) 2007 Rich Sposato
// Permission to use, copy, modify, distribute and sell this software for any
// purpose is hereby granted without fee, provided that the above copyright
// notice appear in all copies and that both that copyright notice and this
// permission notice appear in supporting documentation.
// The author makes no representations about the
// suitability of this software for any purpose. It is provided "as is"
// without express or implied warranty.
////////////////////////////////////////////////////////////////////////////////
// $Id$
#include <loki/CheckReturn.h>
#include <iostream>
#include <string>
using namespace std;
// ----------------------------------------------------------------------------
typedef ::Loki::CheckReturn< bool > BoolReturn;
typedef ::Loki::CheckReturn< string > StringReturn;
typedef ::Loki::CheckReturn< bool , ::Loki::FprintfStderr > BoolReturnStderr;
// ----------------------------------------------------------------------------
bool NoCheckRequired( void )
{
return true;
}
// ----------------------------------------------------------------------------
BoolReturn CheckRequired( void )
{
return BoolReturn( true );
}
// ----------------------------------------------------------------------------
BoolReturnStderr CheckRequiredStderr( void )
{
return BoolReturnStderr( true );
}
// ----------------------------------------------------------------------------
BoolReturn CheckRequired( bool value )
{
// By passing false into CheckRequired, CheckRequired calls an overloaded
// version of CheckRequired, thus demonstrating that one can use a function
// call within the return statement and not have to create a named
// temporary variable.
if ( !value )
return CheckRequired();
return BoolReturn( value );
}
// ----------------------------------------------------------------------------
string GetString( void )
{
return string( "a" );
}
// ----------------------------------------------------------------------------
StringReturn MustUseString( const char * s )
{
return StringReturn( s );
}
// ----------------------------------------------------------------------------
void StringEater( const string & s )
{
(void)s;
}
// ----------------------------------------------------------------------------
int main( unsigned int argc, const char * argv[] )
{
if ( 2 == argc )
{
const char * const a = argv[ argc - 1 ];
// okay to call without storing or using return value.
GetString();
cout << "Called GetString without using return value." << endl;
// Should not assert since caller stores return value.
const string s = MustUseString( a );
cout << "Called MustUseString and stored return value." << endl;
{
// Should not assert since caller passes return value into another
// function, thus converting CheckReturn back into actual type.
StringEater( MustUseString( a ) );
cout <<
"Called MustUseString and passed return value into another function."
<< endl;
}
// This should assert since caller does not check return value.
MustUseString( s.c_str() );
cout << "Should assert before this line! How did we get here?" << endl;
}
// okay to call without storing or using return value.
NoCheckRequired();
cout << "Called NoCheckRequired without using return value." << endl;
// Should not assert since caller stores return value.
bool okay = CheckRequired();
cout << "Called CheckRequired and stored return value." << endl;
if ( CheckRequired( okay ) )
{
cout << "Called CheckRequired and used return value." << endl;
}
{
// Should not assert since caller stores return value ...
BoolReturn checkBool = CheckRequired();
// and then deliberately ignores it before destructor runs.
(bool)checkBool;
cout << "Called CheckRequired, stored return value, and ignored it."
<< endl;
}
{
// This should not assert since caller deliberately chooses to not
// check return value by casting to return value to correct type.
(bool)CheckRequired();
}
{
// This should not assert since caller deliberately chooses to not
// check return value by casting to return value to correct type.
(bool)CheckRequired( false );
cout << "Made a nested call to CheckRequired." << endl;
}
{
BoolReturnStderr check = CheckRequiredStderr();
}
cout << "There should be a error message: \nCheckReturn: return value was not checked" << endl;
// This should assert since caller does not check return value.
CheckRequired();
cout << "Should assert before this line! How did we get here?" << endl;
return 0;
}
// ----------------------------------------------------------------------------
// $Log$
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